NISKINE: Profiling Float Measurements of Near-Inertial Waves and Turbulence

Abstract

Project Summary/Abstract: We propose to deploy arrays of up to 15 chi-augmented EM-APEX profiling floats to characterize sub-inertial balanced vertical shears (and hence gradient Richardson number and horizontal buoyancy-gradients through thermal-wind), the evolution of near-inertial wave energy and energy-flux through interactions with the balanced shear, and turbulent dissipation rates in the region north of the Gulf Stream or North Atlantic Current to contribute to realizing the goals of NISKINE. These instruments provide profile time-series of temperature T, salinity S, horizontal velocity (u, v) and microstructure temperature variance dissipation rate ??. Sampling is planned across both cyclonic and anticyclonic eddies. Two strategies could be used, depending on what would best serve the DRI???s goals: 1. Float arrays could be deployed in late summer to autonomously measure the response to fall and winter storms. This approach has proven successful in ongoing research into dissipation of storm-driven near-inertial waves by the PI???s in the western North Pacific. 2. Alternatively, arrays could be deployed and recovered during shipboard work to take advantage of horizontal structure data from ship surveys and other DRI assets. Interpreting the float data in terms of interactions with the balanced flow would benefit from concurrent measurements of local vorticity and confluence. Interpreting the float data in the context of local wind generation would benefit from simultaneous air-sea flux measurements.

Document Details

Document Type
DoD Grant Award
Publication Date
Jul 26, 2018
Source ID
N000141812598

Entities

People

  • Ren-Chieh Lien

Organizations

  • Office of Naval Research
  • United States Navy
  • University of Washington

Tags

Fields of Study

  • Environmental science

Readers

  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers
  • Oceanography.